2007-06-04 04:00:00 PDT Washington -- There is nothing new - and if history is any indication, nothing temporary -- about the large new temporary worker program that is among the most controversial parts of the giant immigration overhaul to be taken up again by the Senate this week.

The United States already invites three times as many "guest workers" through existing programs as through permanent-job-based channels: more than half a million visas a year, compared with 140,000 permanent-job-based slots. Each year, more than 320,000 of these temporary workers are estimated to stay permanently.

"If you're actually looking at the number of workers, you see that there are far more people entering the labor market through the temporary system than there are through the permanent system," said Deborah Meyers, a senior analyst with the Migration Policy Institute, a nonpartisan think tank.

The proliferation of temporary visas has consumed nearly the whole alphabet, from the well-known H-1B program used by Silicon Valley professionals, to the mysterious new E-3 visa Congress created last year that gives Australians 10,500 extra professional slots.

There are the "John Lennon-Albert Einstein" O visas reserved for "workers of extraordinary ability," the P visas for athletes and entertainers and the R visas for religious workers such as priests, imams, rabbis and monks. L visas go to multinational managers, TN "treaty visas" admit Canadian and Mexican workers under the NAFTA free trade agreement, and F visas go to students who can work part time.

Then there is the smattering of nonwork temporary categories: the K visas for fiances and fiancees, the T visas for victims of trafficking, the U visa for victims of other serious crimes, and the V-3 for "the derivative child of a V-1 or V-2."

Many of these visa categories are uncapped, many allow indefinite renewals and most have been rising sharply.

Temporary work programs have become the first choice of many employers and migrants stymied by the rigid job-based system for permanent residence, or green cards. The H-1B explicitly encourages adjustment to permanent residence by allowing applicants to state that they may abandon their homeland. Many H-1B applicants and their employers see the visa as a byway to a green card.

"The purpose of guest worker programs is to add workers to the labor force but not add settlers to the population," said Philip Martin, a UC Davis economist and leading immigration authority. "But the universal truism is that there is nothing more permanent than temporary workers, whether it's in Europe, whether it's in the Middle East, whether it's in Asia or whether it's in the United States. Guest worker programs tend to get larger, and last longer, than originally anticipated."

The bracero program used in California was created during World War II farm labor shortages. A decade after the war ended it was 10 times its original size. The H-1B program, once seen as a remedy for fixing the Y2K computer problem, is now the largest temporary worker program in the country.

The Swiss were the first Europeans to use guest workers; it was Swiss playwright Max Frisch who famously summarized, "We asked for workers, and people came."

The new Senate proposal -- originally to bring in 400,000 to 600,000 unskilled workers, now cut by half -- is a key ingredient of the immigration grand bargain among a bipartisan group of senators and the White House. The idea is to avoid the mistake of 1986, when Congress granted amnesty to illegal migrants already in the country but provided no legal avenue for future workers. They came anyway, illegally, and today number an estimated 12 million. About 850,000 are believed to arrive illegally each year, and of those about 500,000 stay.

The new plan was to turn the future illegal population into a registered legal one, roughly matching the numbers now coming. But pro-union Democrats, including California Sens. Barbara Boxer and Dianne Feinstein, halved the program to 200,000 and removed a provision that would allow the numbers to rise based on market demand. An amendment to kill the whole program in five years came just one vote shy of bringing down the entire immigration compromise.

Sen. Jon Kyl, R-Ariz., said he will try to reinstate the market-based adjuster so that the 200,000 limit can rise. Supporters say the program is essential to relieving pressure at the border and meeting the demand for labor in construction, restaurants, meat packing and other industries that make heavy use of unskilled migrants.

Many analysts question whether a smaller program can succeed in moving illegal migrants to legal channels.

"In order to do that, one would have to provide sufficient numbers of temporary visas," Meyers said. "If you set an unreasonably low number, people will simply circumvent the program as they do now."

Moreover, the plan calls for temporary workers to come for two-year stints, each followed by one year back in their home country, for a maximum of six years residence. They would not be offered permanent residence, though they could earn points through a separate merit system. Republicans have insisted that "temporary means temporary."

Yet the stricter such rules, the more likely they will be broken, experts said. Unless laws against hiring illegal workers are strictly enforced, such a program could create a new population of illegal immigrants who stay instead of return.

Meyers noted the new temporary workers would not be additions to the population; they would be the same migrants who are arriving today illegally. "It sounds like a large number, but that's because we'd be counting them instead of pretending that they're not here," Meyers said.

The Migration Policy Institute warned that commonly used figures of 1.1 million new legal residents each year grossly undercount actual migrant flows. Illegal migrants should also be counted, along with the 320,000 temporary workers who are believed to stay each year, bringing the actual number of immigrants to the United States each year to more than 1.8 million -- a population double the size of San Jose.

California has more foreign-born workers -- 27 percent of its labor force -- than any other state.

Nor is the U.S. experience occurring in a vacuum. Global migration is rising, driven by powerful demographic, economic and technological forces. Germany, the United Kingdom, Switzerland and other industrialized countries are actively competing worldwide for skilled workers, while experimenting with guest worker programs to fill low-end jobs without drawing large unauthorized populations or adding settlers.

Advanced economies are service-based, with labor markets split between highly skilled knowledge workers and low-skilled service workers. Migrants are increasingly filling lower-wage manufacturing and construction jobs as well. Populations are declining in the wealthier countries of Europe and in Japan -- and would be stagnant in the United States but for migrants -- while fertility remains high in poor countries, creating a magnet for labor on one hand and a ready supply on the other.

South Korea has been drawing large numbers of unauthorized migrants from the Philippines, Sri Lanka, Vietnam, Thailand and Indonesia. It offered an amnesty in 2003 and created a guest worker program that requires workers to leave for a year after every three-year stint and refuses admission to family members to discourage settlement.

If immigrant advocates think the Senate bill is tough on temporary workers, it has nothing on Singapore, which pampers high-skilled migrants but punishes low-skilled workers who overstay their visas with mandatory caning and up to six months in prison.

Temporary worker programs

Immigrant workers can enter the United States through about two dozen temporary visa categories. Congress is considering legislation that would create a new Y visa for a large temporary worker program for unskilled workers now entering the country illegally. Temporary programs have become the primary vehicle for job-based entry, far surpassing employment-based green cards.

Here are some of the current programs:

A visa -- for ambassadors and other diplomats and their families and staffs.

E visa -- treaty trading partners and investors. The latest addition is the new E-3 visa added last year for Australians, following enactment of a free trade agreement with Australia. It essentially removes Australians from the H-1B quotas, which ran out the first day they were offered this year.

H-1B visa -- for specialty occupations, requiring a bachelor's degree or higher. A three-year visa, renewable once. Unlike most visas, H-1B applicants can have a "dual intent" to either return home or seek permanent residence.

H-2A visa -- temporary agricultural workers, used mainly by East Coast growers. Has no annual cap; 76,169 were issued in 2004. Employers complain that it is cumbersome and heavily regulated. Farmworker organizers contend it is rife with abuse.

H-2B visa -- for temporary seasonal workers in everything from the crab industry and Christmas tree farms to ski resorts. Capped at 66,000 a year and heavily subscribed. Congress granted exemptions to expand the program in 2005.

I visa -- for foreign journalists. The visa lasts for the duration of employment.